Blood donations are crucial for patients whose own supply is depleted following an operation or accident, and are globally in short supply. Unfortunately sourcing the blood is only half the battle as complications can arise when storing and administering samples. A new device developed by scientists in Canada is now able to identify “super donors” whose blood can remain viable for much longer both in transit and inside the recipient’s body.
In terms of successful blood transfusions, not all blood is equal. Even within similar blood types there are some donors who produce a higher quality of sample in respect of the red blood cell’s capacity to maintain its structure and functionality for longer. Storage times are crucial in keeping blood banks fully stocked but keeping blood fresh isn’t as simple as popping it in a cool bag.
Our blood is fragile, made up of many components that define its suitability for storage and which patients it can be given to. Clotting factors can make the blood solidify outside of the body and so in transit donations are treated with anticoagulants to prevent thickening and maintain cell viability. Temperature is another key factor, as unfortunately blood is a great culture medium in which to grow bacteria, so samples are processed in a “cold chain management” system from the point of donation, through testing and transportation until they’re eventually administered to a patient, with each sample having an average “shelf life” of about 35 days.
Led by Professor Hongshen Ma, a team of researchers at the University of British Columbia have uncovered a new way of assessing the viability of human blood for transfusion which looks at the deformability of donor red blood cells. Deformability refers to the way red blood cells can change shape during transit, a process that can negatively impact the blood’s ability to circulate in the recipient’s body.
Reporting in the journal Lab on a Chip, Ma and his team used a custom-made microfluidic device to monitor the way the red blood cells of eight recipients changed during storage, which revealed two samples that were significantly better able to maintain their structure. The implication of these stable samples is that an improved understanding of the suitability of a donor’s blood for transfusion will enable practitioners to selectively administer long-circulating red blood cells to more sensitive patients with impaired circulatory systems.
People who need frequent blood transfusions benefit tremendously from red blood cells that are able to appropriately circulate in the blood vessels to deliver oxygen," explained study author Dr Mark Scott, a clinical professor at the University of British Columbia in pathology and laboratory medicine, in a statement. "A method that can swiftly and accurately test the 'squeezability' of these cells can make transfusions safer for these patients and ultimately for anyone who needs a critical transfusion.”
The stability of red blood cells in maintaining their shape and continuing to fit through even small vessels is a crucial factor in their suitability and longevity as transfusion samples, and this new discovery marks the first time researchers have been able to measure this trait in donated blood cells. The phenomenon requires further investigation having only so far been carried out on a small number of samples, but Professor Ma and his team plan to combine with Canadian Blood Services to test further samples and validate the device’s efficiency.
